Peeling aids for patches, transdermal therapeutic systems (TTS), stickers or labels are known for example from GB-A 2 179 910 and EP-B1 0 418 608. Such peeling aids are provided by partially straight or non-linear breaking lines or cuts in the carrier material (peeling foil) and are intended to simplify the mechanical removal of the objects from the carrier material.
Patches, for example transdermal therapeutic systems (TTS), are manufactured in several steps. Frequently, the drug or active agent and the additives are directly worked into the adhesive, so that an easily spreadable mass results containing the drug. This mass is then applied to the surface of a foil as the carrier or peeling foil of the patch, optionally dried and subsequently provided with a cover foil for the patch. It is necessary that such composites are then divided into smaller bands or strips for further processing. Finally, the patches are stamped out of the bands, where normally two gratings result along with the patches.
As an example, FIG. 1 illustrates a top view of a transparent composite comprising a cover foil and an adhesive layer (hatching from top right to left bottom) as well as a peeling foil (hatching from left top to right bottom). When one considers that the peeling foil is on the underside in the drawing plane, the break lines are stamped into the foil from below. According to FIG. 2, again in the drawing plane of the foil, circular cuts to define the patches are also stamped out and run in the axial direction of the band. The break lines cross over the so-defined patches, although the break lines are not interconnected with one another. Thereafter, according to FIG. 3b, the foil band is separated from the material of the cover foil with the adhesive layer, where the band for the carrier or the peeling foil with the individual patches remain as shown in FIG. 3a. Referring to FIG. 4a, cuts are then provided in the foil band of the carrier (peeling foil), which define the peeling foil of the individual patches, whereafter the individual patches are separated out of the foil band. There remains the foil band with the removed patches as shown in FIG. 4b as well as the patches themselves as shown in FIG. 5.
When stamping out such composites of cover foil, adhesive and peeling foil, the conventional stamping forms or dies frequently cause tears to arise in the grating, for example in the cross pieces shown in FIG. 4b. As the end points of the cuts or break lines approach one another, the cross pieces are particularly vulnerable at these locations, because the cross pieces are made as small as possible to save material.
The same problem exists when the break lines are continued into the cross pieces, as shown in the patch of DE-C 3 931 019 in FIG. 1 (not shown here), or the patch shown in FIG. 1 of DE-C 3 344 334 (not shown here) in which the break line 4 cuts into the cross piece. Finally, FIG. 1 of U.S. Pat. No. 4,413,621 illustrates a patch (not shown here) in which the break line 15 cuts into the cross piece.
The object of the present invention is then to provide a patch with peeling foil having a suitable cut or a suitable break line, whereby the described tearing of the cross pieces is avoided and the production yield of patches is increased.
According to the invention, a flat self-adhering drug patch is provided comprising a cover foil and self-adhesive layer containing at least one active agent,
where the patch additionally comprises a removable carrier material (peeling foil) and
where the carrier material extends beyond the patch with cover foil and self-adhesive layer to form a border, wherein the border is provided with two recesses spaced apart from one another, and wherein the respective end points of a break line extend from the recesses, the break line being formed in the carrier material and passing over the self-adhesive layer.
The patch may be a TTS by which the self-adhesive layer contains a drug or active agent.
According to the present invention, a flat self-adhering drug patch is also provided with a cover layer, reservoir containing at least one drug and a membrane which is self-adhesive or carries an adhesive,
wherein the patch additionally comprises a removable carrier material (peeling foil) and
wherein the carrier material extends beyond the patch with its cover foil as well as reservoir and membrane to form a border, wherein the border is provided with two recesses spaced apart from one another and wherein the end points of a break line extend from the recesses, the break line being formed in the carrier material and passing over the self-adhesive layer.
The recesses or cut-outs can be formed to be semi-circular or approximately V-shaped.
The patch can have multiple corners, in particular be square or rectangular or can be elliptical or circular and can be covered by the carrier (peeling foil) which has multiple corners, in particular is square or rectangular. The corners of the multi-cornered carrier can be rounded.
Furthermore, the patch according to the invention can be circular and be covered by a round, triangular, hexagonal or octagonal carrier (peeling foil).
The break lines can be formed as indentations or as a cut or they can also be formed by perforations.
In a preferred embodiment of the patch, the carrier (peeling foil) extends beyond the patch on all sides.
Finally, the patch according to the invention can be provided with bumps or knobs located in or on the carrier. Such bumps are adapted to simplify removal of the patch from a package.
A further embodiment of the invention relates to a method for manufacturing flat self-adhering drug patches according to the invention, including
(a) providing a band of a multi-layer composite comprising
a layer for the cover foil,
a layer for the self-adhesive layer or the reservoir with membrane, and
a layer for the removable carrier material (peeling foil), and providing break lines in the removable carrier material,
(b) making cuts through the layer for the cover foil with the self-adhesive layer or with the reservoir and membrane to define the patches, the cuts made simultaneously or before or after,
(c) making cuts in the layer for the removable carrier material (peeling foil), thereby defining the carrier material (peeling foil) of the patches, the cuts being made simultaneously or before or after,
(d) (i) separating a band of the composite comprising the layer for the cover foil and the self-adhesive layer or the reservoir with membrane, whereby the patches are defined by the cuts in step (b)
(ii) separating a band of the removable the carrier material (peeling foil), whereby the carrier material (peeling foil) of each patch defined by the cuts according to step (c) is removed from the band, and
(iii) separating flat self-adhering drug patches with removable carrier material (peeling foil).
The method according to the invention can be carried out in that one
performs step (a),
thereafter performs step (b),
thereafter separates the band (d) (i),
thereafter performs step (c) and
thereafter separates the band (d) (ii) and the patches (d) (iii).